P6018Can chronic his bundle pacing be safely started in centers with lack of experience of this technique? Data from a multicentric registry

Abstract

Abstract Introduction Right ventricular pacing (RVP) induces ventricular asynchrony in patients with normal QRS and increases the risk of heart failure and atrial fibrillation on long term. His bundle pacing (HBP) is a physiological alternative to RVP. Interest in HBP has been hampered in part by technical challenges and limited implantation tool set. Recent studies assessed feasibility and safety in expert centers with a vast experience of HBP. These results may not apply to less experienced centers. Purpose To evaluate feasibility and safety of permanent his bundle pacing in hospitals with limited technical training to this technique and to evaluate stability of his bundle capture thresholds at 3 months follow up. Methods We included all patients who underwent pacemaker implantation with attempt of HBP in three hospitals between September 2017 and December 2018. All the 5 operators were novice for HBP at the beginning of the study. Selective his bundle capture (HBC) was defined as concordance of QRS and T waves complexes with the native ECG (patients with underlying bundle branch block may normalize), presence of a delay between spike and QRS complex, absence of widening of the QRS at a low pacing output, and recordable his bundle electrogram. At 3 months follow-up, his bundle capture thresholds, R-wave amplitudes and pacing impedances were recorded. Results HPB was successful in 51 of 58 patients (87.9%); selective HBC was obtained in 40 patients while nonselective HBC occurred in 11 patients. Indication for pacemaker implantation was atrioventricular conduction disease in 31 patients (53%), sinus node dysfunction in 5 patients (9%) and AV nodal ablation for non-controlled atrial arrhythmias in 22 patients (38%). AV nodal ablation was performed during the same procedure in 14 patients. The mean procedure duration was 75±8 min, and mean fluoroscopy duration was 10±2 min. The mean HBP threshold was 1.47±0.27 V and did not increase after a 3 months follow-up (1.12±0.18 V). Only 7 patients (14%) had HBP threshold >2V/0.5ms. The mean impedance was 477±37 Ω and slightly decreased at 3 months (364±24Ω). The mean R-wave amplitude was 4.1±1 mV at implantation and 3.2±0.6 mV at 3 months. Bundle branch block correction was achieved in 5 of 7 patients with underlying left bundle branch block. There was no pericardial effusion, no pneumothorax and no device infection. Ventricular lead revision was required at 3 months in one patient for sudden threshold increase, without obvious dislodgement. LBBB correction after HBP Conclusion His bundle pacing performed by novice operators to this technique appeared feasible and safe. The mean HBP threshold did not increase at 3 months follow-up.